Energy Storage Science and Technology ›› 2022, Vol. 11 ›› Issue (1): 176-184.doi: 10.19799/j.cnki.2095-4239.2021.0553

• Energy Storage System and Engineering • Previous Articles     Next Articles

Optimal control strategy for energy storage in island microgrid based on hierarchical control

Yu LI1(), Zhanqiang ZHANG1(), Keqilao MENG2, Haotian WEI1   

  1. 1.The College of Information Engineering, Inner Mongolia University of Technology
    2.The College of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot 010051, Inner Mongolia, China
  • Received:2021-10-20 Revised:2021-11-11 Online:2022-01-05 Published:2022-01-10
  • Contact: Zhanqiang ZHANG E-mail:ly1120850221@163.com;dzxzzq@163.com

Abstract:

In view of the problems of uneven power output and bus voltage drop in the traditional droop control method adopted in the DC microgrid in the energy storage control strategy, the microgrid is proposed to stabilize the DC bus and load constant power operation of the energy storage device in the island mode. The hierarchical control strategy divides the microgrid optimization control process into two layers: the energy storage under the primary control layer is used as the main energy distribution device of the microgrid, and a droop control strategy based on double closed loops is proposed to pass the energy storage battery converter P-f and Q-u carry out double-layer droop control to achieve constant power operation of the load; the energy storage under the secondary control layer is used as a device to stabilize the DC bus voltage and compensate for the primary energy storage. The Synchronous Reference Frame Control (SRFC) strategy is proposed, and add a Self Tuning Filter (STF) in the control to achieve the filtering of harmonics in the AC signal. Finally, Matlab/Simulink is used for simulation verification. The simulation results show that the hierarchical optimization strategy enables the load to run at constant power while stabilizing the DC bus voltage.

Key words: island mode, DC microgrid, energy storage device, droop control, synchronous reference coordinate system control

CLC Number: